Sunday, September 20, 2009

Sunday Essay - Farming, green house gases and the importance of practical experiments- Part Two

This post continues my personal exploration into the world of carbon farming that I began in Sunday Essay - Farming, green house gases and the importance of practical experiments- Part One. There my initial exploration took me somewhat unexpectedly to Peter Andrews and the Natural Farm Sequence Movement.

I say unexpectedly because while I knew of Peter's work I had not connected it with carbon farming, a way of capturing carbon in the soil, improving the soil while reducing CO2. So in my first post I had some fun learning more of Peter's work and especially following the on-line experience of WA Farmer Ian James.

To understand carbon farming, we have to understand soil carbon. Here I quote from Carbon Farmers Australia:

Soil Carbon is that part of the soil that is or has been alive. It is present in litter, roots, insect life, microbes, carbohydrates, fungi, acids and humus. It is also found in soils as carbohydrates, fats, waxes, alkanes, peptides, amino acids, proteins, lipids and organic acids. Soil carbon is produced by biological activity of microbes and fungi, stimulated by the action of roots of plants as they push down through the soil, retreating when the foliage above ground is grazed or harvested, then pushing down through the soil again as the foliage regrows. (There is also mineralised Carbon in the soil which is not organic.) Soil carbon is created when CO2 is absorbed by vegetation, the Oxygen is released and the Carbon is used to make living tissue, such as vegetation, animals that eat vegetation, and humans that can eat both. Some of the retained Carbon returns to the atmosphere as CO2 from respiration (eg. plants ‘breathe out’ CO2 at night). Some of the retained Carbon returns to the atmosphere as CH4 or Methane from the rotting of dead vegetation. But much of the Carbon taken in by the plant enters the top layer of the soil and is held there as humus, and some of it is carried further down to deeper layers of the soil where it can be held for hundreds of years. Depending on what is grown in the soil and how the soil is managed, it can store large amounts of Carbon or it can release large amounts of Greenhouse gases. It is the landholder who decides what the soils contribute to Climate Change.

Now if I interpret this correctly, I am in my own very small way a carbon farmer. I had thought of my approach to gardening with its constant mulching as environmentally sound; fresh vegetables that did not have to be transported grown with minimum water. Now I find that it was more correct than I knew, because in building the humus content I am in fact capturing and storing carbon!

It appears that carbon farming is both a farming approach and an economic movement.

Now here we need to introduce Dr Christine Jones, a retired CSIRO soil scientist who has spent the last two years campaigning around Australia trying to interest farmers in adopting carbon farming techniques. The claims made by Dr Jones are quite startling. In her view, rebuilding carbon-rich agricultural soils is the only real productive, permanent solution to taking excess carbon dioxide from the atmosphere. She stated on the ABC program Future Tense:

This year Australia will emit just over 600 million tonnes of carbon. We can sequester 685 million tonnes of carbon by increasing soil carbon by half a per cent on only 2% of the farms. If we increased it on all of the farms, we could sequester the whole world's emissions of carbon.

You see what I mean by startling. If this claim is correct, it means that to a degree we can have our cake and eat it too by simply improving farming techniques!

Quoting further from the ABC program:

Pip Courtney: With modern farming practices to blame for depleting soil carbon, Dr Jones says nothing short of a radical change in farming methods will turn things around. And that radical change means no more bare soil in grazing or cropping paddocks.

Christine Jones's approach involves getting farmers to keep their ground covered with plants all year round. She says plants are the key to removing excess carbon dioxide from the air, so the more ground cover there is, the more carbon will be stored in the soil, because bare earth gives its carbon up to the atmosphere.

While soil carbon credits won't be part of Australia's emissions trading scheme, which starts next year, Christine Jones is confident that one day Australian farmers will be paid for the carbon they build.

Christine Jones: They can build something like between 25 and 30 tonnes of carbon for every tonne of product that they produce. They can be so far on the right side of the ledger that there's no need to fear being included in an emissions trading scheme.

Dr Jones knew that if her ideas were to carry any weight, that she'd have to show that farmers could profitably graze and crop their land, and maintain permanent ground cover. Two years ago, 18 farmers in three states agreed to trial her ideas. In return, she'd pay them $25 a tonne for the carbon they built.

So far the results appear to be good.

Returning to Peter Andrews, there is a linkage between his work and that of Christine Jones. The ABC program notes that conventional wisdom is that there shouldn't be enough soil moisture to sustain both pasture and a grain crop. But Dr Jones claims farmers can have both, because soil high in organic carbon has better structure, is more fertile, and holds more water.

For his part, Peter Andrews has described his mission in part as the re-hydration of the Australian landscape, the application of farming techniques that build and hold water in the soil.

Two enthusiasts, different approaches, but a common outcome. This links to the heading of this post, the importance of practical experiments. When an approach goes against conventional wisdom as both do, the only way to go is to prove that it works.

Now here we come to growing conflicts that have been bubbling away beneath the surface of public discussion, surfacing briefly from time to time in public in ways that most people ignore because they lack the context.

To understand these conflicts, it is important to recognise that these new farming movements are evolving at the centre of a series of overlapping and often conflicting circles.

To begin with, the idea of keeping water in the soil, on the farm so to speak, means lower river flows. More precisely, it means lower flows in the short term while soil moisture rebuilds. Once soil moisture is re-built, flows will return to normal. However, this can be a bit difficult for people in, say, Adelaide, to accept.

Then, too, the approaches can conflict with conventional approaches to land and water management now enshrined in a variety of legislation and regulation. Take, as one example, the willow. Money is now being spent to remove willows, yet the willow can apparently be very effective as one weapon in the application of the Andrews approach. In fact, the Andrews approach with its emphasis on ground cover re-defines what is a weed.

Or take, as a very small and personal example, previous Sydney water restrictions on the use of hand-held hoses. This put one defined public good, preserving water, in conflict with others. In stopping gardening in the way I did I started importing water through purchase of vegetables grown elsewhere, My point here is simply that in a world of universal rules, it can be very hard to deal with exceptions.

Then there are economic conflicts.

I said that carbon farming was both a farming and economic movement. This is expressed in Michael and Louisa Kielys' Carbon Farmers of Australia, a company that aggregates and sells sono kill direct drill rigil carbon credits.

The Kielys have been campaigning on carbon farming for some time. I first came across them several years ago through Michael's blog. I was very interested, but drifted away when Michael stopped posting in May 2008. However, revisiting the blog this time allowed me to capture some photos that will illustrate the Christine Jones approach.

The photo on the right shows a no kill direct drill rig. Unlike conventional ploughing or indeed no plough weedicides,it leaves the grass; the seed is direct sown and covered.

The photo on the left shows the results in heavy grass. Michael wondered if the sun could get through. I must say that I would too. We do not know whether or not this worked. Normally you would put animals in first to reduce the grass, but there were apparently particular reasons why this was not possible in this case.

One difficulty with the soil carbon approach is captured in the words of Mick Keogh from the Australian Farm Institute no kill in heavy grassquoted on the Future Tense program:

... people have got to remember they're selling the ownership of that carbon in the soil to someone else. They no longer own the carbon in the soil, and if it disappears for any reason, they have to restore it. So I guess the brief message is, for every credit, there's an equal and opposite debit if the reverse action occurs. So if a bushfire comes through, if a big drought occurs, if you decide you want to plough that paddock and that will reduce the soil carbon, then you've got to pay back any earnings that you've made and probably more before you can do that. So people need to understand the double-sided nature of storing carbon in soil.

However, there is also a far more complex problem, and that lies in the conflict between carbon farming and other commonly accepted views that have become enshrined in public policy.

The reason for this can be simply stated: carbon farming proponents argue that the the approach is far more effective in reducing CO2 in the atmosphere than other land use alternatives. This includes locking land up in national parks on one side, plantation farming on the other.

There is no necessary conflict between carbon farming and reforestation as such. Indeed, on-farm reforestation can be critical in building and retaining soil moisture. However, this is reforestation with another purpose in mind; reduced CO2 is a by-blow. The conflict lies in the challenge to existing now deeply enshrined conventions.

This is the area where the underlying debate bubbles into public and where the National Party is playing a role.

The arguments by Joyce and others that plantation farming is not necessarily a good thing have so far been treated in the general media as pandering to their special interest groups. No doubt there is some truth in this. Yet if Christine Jones is in any way right in arguing that we could sequester the world's entire carbon emissions by a change in farming practices, this becomes to my mind the single most important environmental question that we should be discussing.

I do not have the knowledge to make judgements here. However, I am left with a question. Has modern urban Australia moved so far from the country's rural base that we can no longer talk about rural issues in a sensible fashion?

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